Motor gear systems for cameras

ABSTRACT

Gear drive systems used with a camera comprise a housing with an electric drive gear disposed outside of the housing. A host gear is engaged with the drive gear and is rotatably disposed on a stationary shaft extending from the housing. An adapter is attached to the host gear and extends axially outwardly therefrom. A secondary gear is attached to the adapter and comprises a plurality of teeth disposed along an outside diameter. The secondary gear is releasably attached to the adapter by retaining elements and is fixed rotatably to the adapter by registration elements. The secondary gear is attached to the adapter by a push on snap-fit, and is removed from the adapter by being pulled off, thereby avoiding the need for tools to interchange a secondary gear having a desired configuration of teeth to engage a camera optical adjustment element such as a lens ring.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims the benefit of U.S. Provisional PatentApplication No. 62/880,616 filed Jul. 30, 2019, which is herebyincorporated by reference in its entirety.

FIELD

Gear systems as disclosed herein are configured for use with a camera toengage an external gear of a camera component such as a lens forproviding a desired adjustment of one or more optical features, and morespecifically, gear systems as disclosed herein are specially configuredto facilitate an easy gear change without the use of tools or the like.

BACKGROUND

The use of motor gear systems as used in conjunction with cameras suchas film or movie cameras and the like for adjusting such opticalcharacteristics as lens iris and/or focus and/or zoom is known, andconventionally comprises a drive motor that is external from the camera.An example conventional motor gear system 100 is illustrated in FIG. 1A,and generally comprises a motor housing 102 having anelectrically-powered motor (not shown) disclosed in the housing. A drivegear 104 is mounted on a shaft extending outside of the housing that isrotated by the motor. The drive gear 104 includes teeth 106 that areengaged with teeth 108 of a host gear 110 positioned adjacent to and inthe same plane of alignment as the drive gear. The host gear 110 ismounted on a stationary shaft 112 that extends from the housing, whereina bearing is interposed between the shaft 112 and the host gear 110 tofacilitate rotation of the host gear when operated by the drive gear. Inthe example illustrated, axial placement of the host gear 112 on theshaft 112 is maintained or fixed by use of a retaining element such as aC-clip 114 or the like.

The host gear 110 has a set diameter and pitch, in this conventionalmotor gear system a 32 pitch, which may or may not complement the pitchof the particular camera component to be adjusted. Thus, in use, it isoftentimes necessary to attach a differently sized/pitched secondarygear to the host gear that complements a ring gear on the camera for theoptical feature being adjusted. FIG. 1B illustrates a situation wherethe motor gear system 100 is rigged or otherwise mounted to be adjacenta ring gear 120 of a camera element 122, e.g., a lens, to adjust adesired optical feature, in this case, the iris of a lens having a 64pitch. In such a situation, the camera lens iris having a 64 pitchcannot be adjusted by the host gear having a 32 pitch. FIG. 1Aillustrates an example secondary gear 116 having a pitch that isdifferent, in this case, a 64 pitch, then that of the 32 pitch hostgear, wherein the addition of such secondary gear in such conventionalmotor gear system is made by attaching the secondary gear axially to theoutside of the host gear through the use of three screws 118. Onceattached, the motor gear system may be adjusted to place the secondarygear in contact with the same pitch camera ring gear to be adjusted.

While such conventional motor gear systems are useful for adjusting anoptical property of the camera lens, e.g., zoom, focus, iris/aperture orthe like, there are times where a different camera element needs to beadjusted that has either a different pitch or a different depth (whereit is desired to match the depth of the camera ring gear to that of themotor gear system to prevent unwanted wear of the camera ring gear. Theneed to make such adjustments on the run occurs frequently. In suchconventional motor gear system, this requires that the motor gear systembe removed or retracted from the camera to access the screws holding theexisting secondary gear, removing the screws and the existing secondarygear from the host gear, finding the correct secondary gear having thenecessary pitch, attaching the new correct secondary gear by screwedattachment, and then moving the motor gear system into engagement withthe camera ring gear to be adjusted. Alternatively, the entire motorgear system can be changed out with another motor gear system having thecorrect secondary gear already attached thereto. Either way, the processis time-consuming, requires that you have the necessary secondary gearsand tools on hand and/or may require that one have more than one entiremotor gear system handy which still takes time to properly set up withthe camera.

It is, therefore, desired that a motor gear system be constructed in amanner that enables use with cameras, e.g., provides a desired gearedengagement with a camera element gear such a lens gear or the like, thatis specially engineered to enable removal and replacement of a gearelement that engages a camera element gear without removal andreplacement of the gear system and in a manner that avoids the use oftools. It is further desired that such motor gear system be configuredin a manner that permits retrofit use with existing gear motors so thatan entirely new gear motor is not needed. It is further desired that themotor gear system be developed comprising a number of different cameragears providing different gear pitches and/or gear depths that are allinterchangeable in the system to permit a toolless switch out from themotor gear system to thereby enable quick and easy camera reuse in oncean adjustable camera element has been changed.

SUMMARY

Gear drive systems as disclosed herein for use with cameras comprise ahousing including an electric motor. A drive gear is connected with ashaft that extends from the housing, wherein the shaft is connected withthe electric motor. A stationary shaft extends outwardly from thehousing and is positioned a distance from the drive gear shaft. A hostgear is rotatably disposed on the stationary shaft, and the host gear isengaged with the drive gear through respective gear teeth. An adapter isattached to the host gear and extends axially outwardly therefrom.

A secondary gear is releasably attached to the adapter and comprising aplurality of teeth disposed along an outside diameter. One of theadapter and secondary gear include one or more retaining elements forproviding a releasable attachment with a complementary surface featureof the other of the adapter and secondary gear. In an example, the oneor more retaining elements are disposed in the adapter, and thecomplementary surface feature is disposed in the secondary gear. In anexample, the surface feature is a groove disposed circumferentiallyalong at least part of an inside diameter of the secondary gear. In anexample, the one or more retaining elements are disposed along anoutside diameter of the adapter. In an example, the one or moreretaining elements extend a distance outwardly from the outside diameterand are movable inwardly against a spring bias.

The gear drive system includes one or more registration elementsdisposed between the adapter and the secondary gear to rotationally fixthe position of secondary gear relative to the adapter, e.g., when theone or more adapter retaining elements are disposed in the secondarygear surface feature. In an example, the registration element isconnected with and extends from one of the adapter and the secondarygear to fit within a complementary surface feature of the other of theadapter and secondary gear.

Gear drive systems as disclosed herein may be used by attaching thesecondary gear to the adapter. During the attaching step, theregistration element of the adapter is engaged with a surface feature ofthe secondary gear while the two are moved/pushed axially together torotationally fix the secondary gear to the adapter, and the retentionelements of the adapter fit into the surface feature of the secondarygear to provide the releasable attachment therebetween. The secondarygear may be switched out for another secondary gear having differentconfigured teeth by axially pulling the secondary gear away from theadapter, causing the retaining and registration elements to decouplewith surface features of the secondary gear, and installing the desiredsecondary gear in the attaching same manner as described.

Gear drive systems as disclosed herein enable easy and toolless changingof the secondary gear (as called for when being used to adjust differentfeatures of a camera) with secondary gears having differently configuredteeth for purposes of engaging differently configured teeth of a cameraadjustment element such as a lens focus ring or the like. The secondarygear change out is one that involves no tools and only requires that theexisting secondary gear be pulled away from attachment with the adapterand that the new secondary gear be pushed into attachment with theadapter. This configuration enables a user to easily meet accommodateadjusting different camera elements having different gear configurationseasily and quickly while maintaining the use of a single gear drivesystem.

BRIEF DESCRIPTION OF THE DRAWINGS

Gear systems as disclosed herein for use with cameras will now bedescribed by way of example with reference to the accompanying Figures,of which:

FIG. 1A is a perspective view of a conventional motor gear system;

FIG. 1B is a perspective view of a conventional motor gear system asused with a camera;

FIG. 2 is a perspective view of a gear system as disclosed herein shownin an unassembled state;

FIG. 3A is a perspective side view of an example adapter as used withgear systems as disclosed herein;

FIG. 3B is a perspective side view of the adapter of FIG. 3A shown in anunassembled state;

FIG. 3C is a cross-sectional side view of the adapter of FIG. 3A shownin an assembled state;

FIG. 4A is a perspective topside view of an example adapter as attachedto a host gear of gear systems as disclosed herein;

FIG. 4B is a perspective backside view of an example adapter as attachedto a host gear of gear systems as disclosed herein;

FIG. 5A is a perspective side view of an example camera gear of gearsystems as disclosed herein;

FIG. 5B is a cross-sectional side view of the camera gear of FIG. 5A;

FIG. 5C is a cross-sectional side view of a section of the camera gearof FIG. 5B;

FIG. 6 is a perspective frontside view of an example adapter and cameragear of gear systems as disclosed herein in an unassembled state;

FIG. 7 is a perspective frontside view of the adapter and camera gear ofFIG. 6 in an assembled state;

FIG. 8 is a perspective view of differently configured example cameragears of gear systems as disclosed herein; and

FIG. 9 is a perspective view of an example motor gear system asdisclosed herein as used with a camera.

DESCRIPTION

Motor gear systems as disclosed herein are generally configured for usein adjusting an optical characteristic of a camera, such as a movie or afilm camera and the like, wherein such optical characteristic comprisinga gear ring for adjustment, e.g., lens characteristic such as theiris/aperture, zoom, and/or focus. In an example, the motor gear systemcomprises an adapter that is fixed to a host gear of an existing motorgear system and that is specially configured to accommodate snap-onattachment with one of a number of secondary gears, of different pitchand/or depth as called for by the particular use application, whereinsuch secondary gears are also specially configured to accommodate thesnap-on attachment with the adapter. Configured in this manner, changesto the motor gear system to accommodate a change to the camera opticalfeature being adjusted is made quickly and without the need for tools orback up motor gear systems.

FIG. 2 illustrates an example motor gear system 200 as disclosed hereinshowing a housing 202 comprising an electric motor (not shown) disposedtherein that operates to rotate a drive gear 204. A host gear 206 isshown in an unmounted state away from a stationary shaft 208 upon whichthe host gear is placed. In an example, a bearing is interposed betweenthe host gear and the shaft to facilitate rotation of the host gear onthe shaft with actuated by the drive gear. An adapter 210 is attached toan axial end of the host gear (as discussed in detail below), and isconfigured to accommodate a snap-on attachment of one of many differentsecondary gears 212, 214, 216, 218, 220 and 222 as illustrated which mayhave a different pitch and or have a different depth as called for by aparticular end-use application, i.e., the configuration of the cameraring gear being engaged to change the desired camera optical property.In an example, each of the different secondary gears has anidentification indicia along an outside surface indicating theparticular pitch and/or depth for purposes of easy identification for auser.

FIG. 3A illustrates an example adapter 300 as used with motor gearsystems as disclosed herein in an assembled state. The adapter 300 has acircular shape with an opening 302 having an inside diameter and an edgesurface 304 having an outside diameter. The adapter has a frontsidesurface 306 on one axial end and a backside surface 308 on an opposedaxial end. In an example, the adapter backside surface 308 is generallyflat for attaching against an axial end of the motor gear system hostgear. The adapter opening 302 is generally sized to accommodate accessto a retaining element used to attach the host gear to the stationaryshaft to thereby enable removal of the combined adapter and host gearfrom the stationary shaft if so needed. The adapter includes mountingholes 310 extending through a thickness of the adapter and positioned toaccommodate using fastening members, e.g., screws, for attaching theadapter to the host gear. In an example, the adapter comprises threemounting holes positioned in a location corresponding to mounting pointson the host gear.

In an example, moving axially from the backside surface 308, the edgesurface 304 extends axially a partial distance along the thickness ofthe adapter and comprises one or more retaining elements 312 disposedradially therein. In an example, the retaining elements 312 areconfigured projecting outwardly a partial distance from the edge surface304 and capable of retracting inwardly against an outward spring bias toa position extending slightly outwardly from the edge surface 304.

FIG. 3B illustrates the example adapter 300 in an unassembled state, inan example the retaining elements 312 may be provided in the form of aball 314 and respective spring 316 that are disposed in a radiallyinwardly recessed cavity 318 sized to accommodate the same. In anexample, the cavity is sized slightly larger than ball 314 therebyenable the ball to project outwardly a partial distance from the cavitywhile retaining the ball and spring within the cavity by a processcalled staking. In an example, the adapter may comprise one or more ofsuch retaining elements 312 as useful for enabling a snap-on attachmentand retention of a secondary gear. In an example, the adapter comprisestwo or more such retaining elements, and in the illustrated examplecomprises approximately five retaining elements that are equidistantlyspaced apart along the edge surface 304 for the purpose of providing asecure snap-on attachment and retention of the secondary gear.

With reference to FIGS. 3A and 3B, the example adapter 300 includes arecessed edge section 320 extending axially from the edge surface 304 tothe front side surface 306, wherein the recessed edge section has anoutside diameter that is less than that of the edge surface 304. Therecessed edge section 320 is configured to accommodate fitment of asecondary gear inside diameter section therein as described below. In anexample, the recessed edge section 320 includes one or more registrationelements 322 disposed therein for the purpose of engaging acomplimentary registration feature of the secondary gear during fitmentto rotational fix the secondary gear and adapter together. In anexample, the one or more registration elements 322 extend axially alongthe recessed edge section 320.

In an example, the registration elements 322 are in the form of pinsthat fit radially into respective recessed grooves 324 disposed in therecessed edge section. In an example, the adapter includes holes 326extending a partial axial depth into a shoulder section 328 of theadapter between the edge surface 304 and recessed edge section 320. Eachhole 326 is sized and positioned to accommodate an end portion a pinthat is disposed in a groove 324 and axially fixes the pin 322 to theadapter. In an example, the adapter comprises more than one of theregistration elements or pins 322 as useful to fix the rotationalplacement of the secondary gear on the adapter, i.e., to prevent thesecondary gear from rotating relative to the adapter once the secondarygear is attached with the adapter. In an example, the adapter comprisesfive pins that are equidistantly spaced apart along the recessed edgesection 320.

In an example, the adapter 300 front side surface 306 comprises recessedsections 330 that extend axially inwardly a partial depth for purposesof weight reduction. In an example, the adapter includes three recessedsections 330 of approximately equal configuration and that are separatedby web portions 332, wherein the mounting holes 310 for attaching theadapter 300 to the host gear are disposed through the web portions 332.It is to be understood that the recessed sections 330 are optional. Inan example, the adapter may be formed from a structurally rigid materialsuch as a metal or metal alloy that may be formed by mold or machineprocess. In an example, the adapter is formed from aluminum by machineprocess, and may or may not be anodized.

FIG. 3C illustrates the example adapter 300 in cross-section showing themounting hole 310 extending between the frontside and backside surfaces306 and 308, the retaining element 322 disposed in the recessed edgesection 320 and extending into the hole, as well as the optionalrecessed section 330 in the frontside surface 306, and the retainingelement ball 314 and spring 316 disposed in the radially inwardlyrecessed cavity 318 along the edge surface 304.

FIGS. 4A and 4B illustrate an assembly 400 comprising an example adapter300 as disclosed herein as combined with the host gear 206. FIG. 4Ashows the assembly 400 with the adapter 300 on top as attached to thehost gear 206 by fasteners 402 in the form of screws disposed into themounting holes and engaged with threaded holes in the host gear. Acenter section 404 of the host gear can be seen through the adapteropening. FIG. 4B shows the assembly 400 with the host gear 206 on topand shows threaded inserts 406 disposed in holes accommodating theadapter fasteners therein 402. As illustrated, the adapter edge surface304 is sized having an outside diameter that is greater than that of thehost gear. Also shown is a bearing 410 that is disposed in the centersection 404 of the host gear for facilitating rotation of the assemblyon the stationary shaft of the motor gear system.

FIGS. 5A and 5B illustrate an example secondary gear 500 as disclosedherein and as configured to facilitate snap-on attachment with theadapter. In an example, the secondary gear 500 comprises an outsidediameter comprising a plurality of teeth 502 that are sized and spacedapart as called for by a particular end use application, e.g., to have apitch that matches the pitch of a ring gear on a camera to be rotated byengagement of the secondary gear. Additionally, the secondary gear mayhave an axial depth as called for by the end-use application, e.g., toclosely match the axial depth of the camera ring gear to be engaged androtated. The secondary gear includes a frontside axial surface 504, anopposed backside axial surface 506, and an inside diameter 508 extendingtherebetween.

Also referring to FIGS. 5B and 5C, moving axially inwardly from thefrontside surface 504, the inside diameter 508 includes a recessedsection 510 that leads to a recessed groove 512 extendingcircumferentially around the inside diameter. The recessed section 510and recessed groove 512 are configured to accommodate engagement of theadapter respective edge surface and retaining elements therein. Movingaxially inwardly from the recessed groove 512, the inside diameterincludes a shoulder section 514 that transitions from the recessedgroove 512 to a reduced diameter section 516. The reduced diametersection 516 includes one or more recessed registration grooves 518 aredisposed a partial depth therein and that extends axially a partiallength of the reduced diameter section.

The registration grooves are configured to accommodate engagement andplacement of the adapter registration elements or pins to therebyrotationally fix the secondary gear relative to the adapter. In anexample, the secondary gear comprises five such registration grooves 518corresponding to the number of adapter registration elements asdisclosed above in an example adapter. In an example, secondary gears asdisclosed herein may be formed from a structurally rigid material suchas a metal or metal alloy that may be formed by mold or machine process.In an example, the adapter is formed from aluminum by machine process,and may or may not be anodized.

Configured in this manner, the secondary gear attaches to the adapter byaxially aligning the frontside of the adapter with the frontside of thesecondary gear, pressing the adapter and secondary gear together causingthe adapter recessed edge section and registration elements to move intothe reduce diameter section of the secondary gear and engagingrespective registration grooves disposed therein, and continuing topress together to cause the adapter registration elements to betemporarily retracted and then extend by spring force into the secondarygear recessed groove, thereby providing a snap-on fit between theadapter and the secondary gear that fixes the gear rotationally to theadapter for use.

FIG. 6 illustrates an example adapter and secondary gear assembly 600 inan unassembled state, showing an example adapter 300 and secondary gear500 and the various features of each as disclosed and illustratedindividually above. FIG. 7 illustrates an example adapter and secondarygear assembly 600 comprising an example adapter 300 and secondary gear500 in an assembled state, combined together the manner described aboveby snap on or snap fit attachment, wherein the retaining elements of theadapter are disposed in the secondary gear recessed groove to provideremovable axial fitment therebetween, and wherein the adapterregistration elements are disposed in the secondary gear registrationgrooves to rotationally fix the secondary gear and adapter together.

FIG. 8 illustrates an assembly of secondary gears 700 comprising anumber of secondary gears each comprising the same inside diameterconfiguration as disclosed above, while having an outside diameter ofteeth that are configured differently and/or having an axial depth thatis different to complement a number of different camera ring gear teethand depth configurations to enable the motor gear system as disclosedherein to function to adjust a number of different camera opticalcharacteristics. In an example, the secondary ring gears may each have adifferent number or pitch of teeth, as well as a different axial depth,configured to best accommodate the different configuration of cameraring gears that may be encountered during a camera use application.

In an example, the secondary gears may be configured to provide a 32pitch, 48 pitch, 64 pitch, and M0.5, M0.6, M.08 in SI or metric systemas well as having a different number of teeth that in an example mayrange from 76 to 154 teeth depending on the particular application. Inan example, an example motor gear system as disclosed herein may includesix differently configured secondary gears, wherein a first secondarygear 702 is 76 teeth and M0.8/32 pitch (wide gear), a second secondarygear 704 is 76 teeth and M0.8/32 pitch (narrow gear), a third secondarygear 706 is 102 teeth and M0.6, a fourth secondary gear 708 is 122 teethand M0.5, a fifth secondary gear 710 is 154 teeth and M0.6/64 pitch asixth secondary gear 712 is 116 teeth and 48 pitch.

FIG. 9 illustrates an example motor gear system 800 as disclosed hereinand as mounted for use to adjust an optical feature of a camera 802. Themotor gear system comprising the adapter 300 and a secondary gear 500that has been attached together as disclosed above is rigged orotherwise mounted to be adjacent a ring gear 804 of the camera lens 806to adjust a desired optical feature, in this case, the iris of a lenshaving a 64 pitch. Thus, the stationary gear 500 is configured having a64 pitch to complement the camera ring gear 502. In this example, thecamera lens includes a focus ring gear 808 that has a 32 pitchconfiguration. If desired, the example motor gear system 800 can beadapted to adjust the focus ring gear 808 by removing the existingsecondary gear 500 of 64 pitch by pulling it axially away from theadapter, and then attaching the correct secondary gear having a 32 pitchby pressing together with the adapter to provide a snap-on or snap-fitattachment.

A feature of motor gear systems as disclosed herein is the ability toreplacement secondary gears as needed to adjust different camera opticalproperties without having to use tools by a simple press on a pull offattachment. This feature enables a user to continue using a single motorgear housing comprising the adapter attached with the host gear, andsimply changing out the secondary gear that is configured as needed toadjust the camera optical feature, thus avoiding the need to havemultiple motor gear systems on hand, and reducing the downtimeassociated with make such changes.

While certain types and constructions of example motor gear systems havebeen disclosed and illustrated, it is to be understood that suchexamples have been provided for purposes of reference and illustration,and that such motor gear systems as disclosed herein should not belimited to the particular embodiments discussed above. For example,while a particular type of mechanism has been disclosed and illustratedfor providing axial retention of a secondary gear on the adapter it isto be understood that other mechanisms capable of providing a similarsnap-on fitment between the two are intended to be within the scope ofmotor gear systems as disclosed herein. The same is true for theparticular mechanism disclosed and illustrated for fixing rotationalattachment of the secondary gear to the adapter, and all such othermechanisms capable of providing such fixed rotational attachment areintended to be within the scope of motor gear systems as disclosedherein. Further, while an example adapter has been disclosed ascomprising both the retention elements and registration elements, it isto be understood that one or both such elements may be embodied in thesecondary gear and the adapter may be configured to accommodate suchdifferent placement of these elements.

What is claimed is:
 1. A gear drive system for use with a cameracomprising: a housing comprising an electric motor; a drive gearconnected with a shaft extending from the housing, wherein the shaft isconnected with the electric motor; a stationary shaft extending fromhousing positioned a distance from the drive gear shaft; a host geardisposed on the stationary shaft, the host gear being engaged with thedrive gear; and an adapter attached to the host gear; a secondary gearattached to the adapter, wherein one of the adapter and secondary gearinclude one or more retaining elements for providing a releasableattachment with a complementary surface feature of the other of theadapter and secondary gear.
 2. The gear drive system as recited in claim1 wherein the one or more retaining elements are disposed in theadapter, and the complementary surface feature is disposed in thesecondary gear.
 3. The gear drive system as recited in claim 2 whereinthe one or more retaining elements are disposed along an outsidediameter of the adapter.
 4. The gear drive system as recited in claim 3wherein the surface feature is a groove disposed circumferentially alongat least part of an inside diameter of the secondary gear.
 5. The geardrive as recited in claim 3 wherein the one or more retaining elementsextend a distance outwardly from the outside diameter and are movableinwardly against a spring bias.
 6. The gear drive system as recited inclaim 1 wherein the secondary gear has an outside diameter comprisinggear teeth disposed therearound.
 7. The gear drive system as recited inclaim 6 comprising a number of secondary gears, wherein each one has adifferent number of gear teeth.
 8. The gear drive system as recited inclaim 1 further comprising a registration element between the adapterand secondary gear to rotationally fix the adapter to the secondarygear.
 9. The gear drive system as recited in claim 7 wherein theregistration element is connected with and extends from one of theadapter and the secondary gear to fit within a complementary surfacefeature of the other of the adapter and secondary gear.
 10. A gear drivesystem for use with a camera comprising: a housing comprising anelectric motor; a drive gear connected with a shaft extending from thehousing, wherein the shaft is connected with the electric motor; astationary shaft extending from housing positioned a distance from thedrive gear shaft; a host gear disposed on the stationary shaft, the hostgear being engaged with the drive gear; an adapter attached to an axialend of the host gear; and a secondary gear positioned against an axialend of the adapter opposite the host gear, wherein the adapter comprisesa number of spring biased retaining elements that are disposed within acomplementary surface feature of the secondary gear to provide areleasable attachment between the adapter and secondary gear.
 11. Thegear drive system as recited in claim 10 wherein the retaining elementsare disposed along an outside diameter of the adapter.
 12. The geardrive system as recited in claim 10 wherein the retaining elements arespaced apart equidistantly along the outside diameter.
 13. The geardrive system as recited in claim 12 wherein the surface featurecomprises a groove disposed along an inside diameter of the secondarygear, and wherein the secondary gear inside diameter is sized to fitover the adapter outside diameter.
 14. The gear drive system as recitedin claim 10 further comprising a registration element interposed betweenthe adapter and the secondary gear to rotatably fix the adapter andsecondary gear together.
 15. The gear drive system as recited in claim14 wherein the registration element is attached to the adapter andextends outwardly a distance therefrom and is disposed within acomplementary surface feature of the secondary gear.
 16. The gear drivesystem as recited in claim 14 wherein the registration element isdisposed within a recessed section that extends axially along the insidediameter.
 17. The gear drive system as recited in claim 10 wherein thesecondary gear comprising an outside diameter with a number of gearteeth disposed thereon, and wherein the gear drive system comprises anumber of secondary gears each having a different number of gear teethand are each attach interchangeably with the adapter.
 18. A method forattaching and removing a secondary gear as used with a camera gear drivesystem comprising a housing with an electric motor, a drive gearextending from the housing and connected with the electric motor, and ahost gear extending from the housing and engaged with the drive gear,the method comprising the steps of: attaching a secondary gear to anadapter, wherein the adapter is attached and extends from the host gear,wherein one of the adapter and the secondary gear includes retainingelements that fit within respective surface features of the other of theadapter and secondary gear, and wherein the step of attaching involvespushing the secondary gear axially against the adapter; and removing thesecondary gear from the adapter by pulling the secondary gear away fromthe adapter.
 19. The method as recited in claim 18 wherein, during thestep of attaching, rotationally fixing placement of the secondary gearrelative to the adapter through the use of one or more registrationelements interposed between the adapter and the secondary gear.
 20. Themethod as recited in claim 1 further comprising repeating the step ofattaching using a secondary gear having a different number of teeth thanthe secondary gear removed from the adapter.